Left ventricular dual-energy digital subtraction angiography: a motion immune digital subtraction technique

Digital subtraction angiography (DSA) allows quantitative analysis of ventricular function via densitometric and parametric imaging techniques. However, DSA is limited by the artifacts in temporal subtraction images that result from patient and cardiac motion. Dual-energy subtraction imaging is insensitive to motion. This study evaluated the initial application of dual-energy subtraction in cardiac patients. The image quality of dual-energy subtraction left ventriculograms obtained from a pulmonary artery injection of contrast was assessed in 13 patients, ranging in weight from 54 to 100 kg. The dual-energy images were compared with left ventricular images obtained using standard left ventricular injection cine angiography. End-systolic and end-diastolic ventricular volumes calculated from the cine (C) and dual-energy (DE) images using the Area-Length method were compared. The resulting regression line was DE = 0.98 C+ 7.0 ml, and the r value was 0.987. Dual-energy subtraction provided good left ventricular visualization, free from misregistration artifacts, even during patient motion.